The present invention relates to an NC (Numerical Control) apparatus, and more particularly to an NC apparatus in which the number of interfaces is reduced and in which the size of the apparatus is made small.
FIG. 1 is a schematic diagram showing an example of a conventional NC apparatus. In this drawing, reference numerals 10 and 20 designate an NC apparatus and a machine which is an object to be controlled. The NC apparatus 10 is composed of a body 11, an NC operation board 12, a machine operation board 13 and interfaces 14 and 15. The NC operation board 12 and the machine operation board 13 are connected with the body 11 through the interfaces 14 and 15, respectively. The machine 20 is connected to the body 11 through an interface 16.
FIG. 2 is a block diagram showing the arrangement of the NC apparatus 10 of FIG. 1. In this drawings, the body 11 is composed of a control section 11A, an operation section 11B, a storage section 11C, an output section 11D, and a sequencer section 11E. The elements in the drawing are the same as FIG. 1.
The NC operation board 12 is connected with the body 11 through the interface 14. This connection is performed by means of an all-purpose serial data transmission system based on the RS-232C system defined by the ISO standard. FIG. 3 shows an example of the connection between an interface section 12A of the NC operation board 12 and the interface 14 of the body 11 according to the RS-232C system.
FIG. 4 shows the arrangement of the interface 15, which is composed of a parallel contact input/output circuit including an input circuit 15A and an output circuit 15B. The input circuit 15A receives a signal from an operation switch 131 of the machine operation board 13 by means of a receiver circuit 151 and transmits the signal to the body 11. The output circuit 15B includes a transistor TR which is driven by a signal from the body 11 and to produce an output signal. The output signal from the transistor TR actuates a relay 132 of the machine operation board 13 to light a lamp.
FIG. 5 shows an example of the machine operation board 13.
The operation of the apparatus will be described.
Necessary programs, data, etc. are entered through the NC operation board 12, and the apparatus is made ready to operate. Then, a start instruction is given through the machine operation board 13 and the machine 20 is controlled with the output from the output section 11D of the body 11. At the same time, the machine operation board 13 reads operating information from the sequencer section 11E of the body 11.
The machine operating information is composed of an operation switch input for causing the machine 20 to operate, an indicator lamp output for confirming the operating condition of the machine 20, etc. The operating switch input includes an NC mode signal switch input, an automatic start signal switch input, an automatic signal switch input, etc. The indicator lamp output includes an auto-start signal lamp output, an auto-stop signal lamp output, an alarm signal lamp output, etc. In this manner, inputting to the body 11 through the NC operation board 12 as well as operating through the machine operation board 13 are attained.
In the conventional NC apparatus, however, the body 11 is always connected with the NC operation board 12 and the machine operation board 13 so that there is a disadvantage that a wide space is required and respective interfaces are required for the boards 12 and 13.